1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.graphics; 18 19 import android.os.Parcel; 20 import android.os.Parcelable; 21 import android.util.DisplayMetrics; 22 23 import java.io.OutputStream; 24 import java.nio.Buffer; 25 import java.nio.ByteBuffer; 26 import java.nio.IntBuffer; 27 import java.nio.ShortBuffer; 28 29 public final class Bitmap implements Parcelable { 30 31 /** 32 * Indicates that the bitmap was created for an unknown pixel density. 33 * 34 * @see Bitmap#getDensity() 35 * @see Bitmap#setDensity(int) 36 */ 37 public static final int DENSITY_NONE = 0; 38 39 /** 40 * Note: mNativeBitmap is used by FaceDetector_jni.cpp 41 * Don't change/rename without updating FaceDetector_jni.cpp 42 * 43 * @hide 44 */ 45 public final int mNativeBitmap; 46 47 /** 48 * Backing buffer for the Bitmap. 49 * Made public for quick access from drawing methods -- do NOT modify 50 * from outside this class. 51 * 52 * @hide 53 */ 54 public byte[] mBuffer; 55 56 @SuppressWarnings({"FieldCanBeLocal", "UnusedDeclaration"}) // Keep to finalize native resources 57 private final BitmapFinalizer mFinalizer; 58 59 private final boolean mIsMutable; 60 private byte[] mNinePatchChunk; // may be null 61 private int[] mLayoutBounds; // may be null 62 private int mWidth = -1; 63 private int mHeight = -1; 64 private boolean mRecycled; 65 66 // Package-scoped for fast access. 67 /*package*/ int mDensity = sDefaultDensity = getDefaultDensity(); 68 69 private static volatile Matrix sScaleMatrix; 70 71 private static volatile int sDefaultDensity = -1; 72 73 /** 74 * For backwards compatibility, allows the app layer to change the default 75 * density when running old apps. 76 * @hide 77 */ 78 public static void setDefaultDensity(int density) { 79 sDefaultDensity = density; 80 } 81 82 /*package*/ static int getDefaultDensity() { 83 if (sDefaultDensity >= 0) { 84 return sDefaultDensity; 85 } 86 sDefaultDensity = DisplayMetrics.DENSITY_DEVICE; 87 return sDefaultDensity; 88 } 89 90 /** 91 * @noinspection UnusedDeclaration 92 */ 93 /* Private constructor that must received an already allocated native 94 bitmap int (pointer). 95 96 This can be called from JNI code. 97 */ 98 /*package*/ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk, 99 int density) { 100 this(nativeBitmap, buffer, isMutable, ninePatchChunk, null, density); 101 } 102 103 /** 104 * @noinspection UnusedDeclaration 105 */ 106 /* Private constructor that must received an already allocated native 107 bitmap int (pointer). 108 109 This can be called from JNI code. 110 */ 111 /*package*/ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk, 112 int[] layoutBounds, int density) { 113 if (nativeBitmap == 0) { 114 throw new RuntimeException("internal error: native bitmap is 0"); 115 } 116 117 mBuffer = buffer; 118 // we delete this in our finalizer 119 mNativeBitmap = nativeBitmap; 120 mFinalizer = new BitmapFinalizer(nativeBitmap); 121 122 mIsMutable = isMutable; 123 mNinePatchChunk = ninePatchChunk; 124 mLayoutBounds = layoutBounds; 125 if (density >= 0) { 126 mDensity = density; 127 } 128 } 129 130 /** 131 * <p>Returns the density for this bitmap.</p> 132 * 133 * <p>The default density is the same density as the current display, 134 * unless the current application does not support different screen 135 * densities in which case it is 136 * {@link android.util.DisplayMetrics#DENSITY_DEFAULT}. Note that 137 * compatibility mode is determined by the application that was initially 138 * loaded into a process -- applications that share the same process should 139 * all have the same compatibility, or ensure they explicitly set the 140 * density of their bitmaps appropriately.</p> 141 * 142 * @return A scaling factor of the default density or {@link #DENSITY_NONE} 143 * if the scaling factor is unknown. 144 * 145 * @see #setDensity(int) 146 * @see android.util.DisplayMetrics#DENSITY_DEFAULT 147 * @see android.util.DisplayMetrics#densityDpi 148 * @see #DENSITY_NONE 149 */ 150 public int getDensity() { 151 return mDensity; 152 } 153 154 /** 155 * <p>Specifies the density for this bitmap. When the bitmap is 156 * drawn to a Canvas that also has a density, it will be scaled 157 * appropriately.</p> 158 * 159 * @param density The density scaling factor to use with this bitmap or 160 * {@link #DENSITY_NONE} if the density is unknown. 161 * 162 * @see #getDensity() 163 * @see android.util.DisplayMetrics#DENSITY_DEFAULT 164 * @see android.util.DisplayMetrics#densityDpi 165 * @see #DENSITY_NONE 166 */ 167 public void setDensity(int density) { 168 mDensity = density; 169 } 170 171 /** 172 * Sets the nine patch chunk. 173 * 174 * @param chunk The definition of the nine patch 175 * 176 * @hide 177 */ 178 public void setNinePatchChunk(byte[] chunk) { 179 mNinePatchChunk = chunk; 180 } 181 182 /** 183 * Sets the layout bounds as an array of left, top, right, bottom integers 184 * @param bounds the array containing the padding values 185 * 186 * @hide 187 */ 188 public void setLayoutBounds(int[] bounds) { 189 mLayoutBounds = bounds; 190 } 191 192 /** 193 * Free the native object associated with this bitmap, and clear the 194 * reference to the pixel data. This will not free the pixel data synchronously; 195 * it simply allows it to be garbage collected if there are no other references. 196 * The bitmap is marked as "dead", meaning it will throw an exception if 197 * getPixels() or setPixels() is called, and will draw nothing. This operation 198 * cannot be reversed, so it should only be called if you are sure there are no 199 * further uses for the bitmap. This is an advanced call, and normally need 200 * not be called, since the normal GC process will free up this memory when 201 * there are no more references to this bitmap. 202 */ 203 public void recycle() { 204 if (!mRecycled) { 205 mBuffer = null; 206 nativeRecycle(mNativeBitmap); 207 mNinePatchChunk = null; 208 mRecycled = true; 209 } 210 } 211 212 /** 213 * Returns true if this bitmap has been recycled. If so, then it is an error 214 * to try to access its pixels, and the bitmap will not draw. 215 * 216 * @return true if the bitmap has been recycled 217 */ 218 public final boolean isRecycled() { 219 return mRecycled; 220 } 221 222 /** 223 * Returns the generation ID of this bitmap. The generation ID changes 224 * whenever the bitmap is modified. This can be used as an efficient way to 225 * check if a bitmap has changed. 226 * 227 * @return The current generation ID for this bitmap. 228 */ 229 public int getGenerationId() { 230 return nativeGenerationId(mNativeBitmap); 231 } 232 233 /** 234 * This is called by methods that want to throw an exception if the bitmap 235 * has already been recycled. 236 */ 237 private void checkRecycled(String errorMessage) { 238 if (mRecycled) { 239 throw new IllegalStateException(errorMessage); 240 } 241 } 242 243 /** 244 * Common code for checking that x and y are >= 0 245 * 246 * @param x x coordinate to ensure is >= 0 247 * @param y y coordinate to ensure is >= 0 248 */ 249 private static void checkXYSign(int x, int y) { 250 if (x < 0) { 251 throw new IllegalArgumentException("x must be >= 0"); 252 } 253 if (y < 0) { 254 throw new IllegalArgumentException("y must be >= 0"); 255 } 256 } 257 258 /** 259 * Common code for checking that width and height are > 0 260 * 261 * @param width width to ensure is > 0 262 * @param height height to ensure is > 0 263 */ 264 private static void checkWidthHeight(int width, int height) { 265 if (width <= 0) { 266 throw new IllegalArgumentException("width must be > 0"); 267 } 268 if (height <= 0) { 269 throw new IllegalArgumentException("height must be > 0"); 270 } 271 } 272 273 /** 274 * Possible bitmap configurations. A bitmap configuration describes 275 * how pixels are stored. This affects the quality (color depth) as 276 * well as the ability to display transparent/translucent colors. 277 */ 278 public enum Config { 279 // these native values must match up with the enum in SkBitmap.h 280 281 /** 282 * Each pixel is stored as a single translucency (alpha) channel. 283 * This is very useful to efficiently store masks for instance. 284 * No color information is stored. 285 * With this configuration, each pixel requires 1 byte of memory. 286 */ 287 ALPHA_8 (2), 288 289 /** 290 * Each pixel is stored on 2 bytes and only the RGB channels are 291 * encoded: red is stored with 5 bits of precision (32 possible 292 * values), green is stored with 6 bits of precision (64 possible 293 * values) and blue is stored with 5 bits of precision. 294 * 295 * This configuration can produce slight visual artifacts depending 296 * on the configuration of the source. For instance, without 297 * dithering, the result might show a greenish tint. To get better 298 * results dithering should be applied. 299 * 300 * This configuration may be useful when using opaque bitmaps 301 * that do not require high color fidelity. 302 */ 303 RGB_565 (4), 304 305 /** 306 * Each pixel is stored on 2 bytes. The three RGB color channels 307 * and the alpha channel (translucency) are stored with a 4 bits 308 * precision (16 possible values.) 309 * 310 * This configuration is mostly useful if the application needs 311 * to store translucency information but also needs to save 312 * memory. 313 * 314 * It is recommended to use {@link #ARGB_8888} instead of this 315 * configuration. 316 * 317 * @deprecated Because of the poor quality of this configuration, 318 * it is advised to use {@link #ARGB_8888} instead. 319 */ 320 @Deprecated 321 ARGB_4444 (5), 322 323 /** 324 * Each pixel is stored on 4 bytes. Each channel (RGB and alpha 325 * for translucency) is stored with 8 bits of precision (256 326 * possible values.) 327 * 328 * This configuration is very flexible and offers the best 329 * quality. It should be used whenever possible. 330 */ 331 ARGB_8888 (6); 332 333 final int nativeInt; 334 335 @SuppressWarnings({"deprecation"}) 336 private static Config sConfigs[] = { 337 null, null, ALPHA_8, null, RGB_565, ARGB_4444, ARGB_8888 338 }; 339 340 Config(int ni) { 341 this.nativeInt = ni; 342 } 343 344 static Config nativeToConfig(int ni) { 345 return sConfigs[ni]; 346 } 347 } 348 349 /** 350 * Copy the bitmap's pixels into the specified buffer (allocated by the 351 * caller). An exception is thrown if the buffer is not large enough to 352 * hold all of the pixels (taking into account the number of bytes per 353 * pixel) or if the Buffer subclass is not one of the support types 354 * (ByteBuffer, ShortBuffer, IntBuffer). 355 */ 356 public void copyPixelsToBuffer(Buffer dst) { 357 int elements = dst.remaining(); 358 int shift; 359 if (dst instanceof ByteBuffer) { 360 shift = 0; 361 } else if (dst instanceof ShortBuffer) { 362 shift = 1; 363 } else if (dst instanceof IntBuffer) { 364 shift = 2; 365 } else { 366 throw new RuntimeException("unsupported Buffer subclass"); 367 } 368 369 long bufferSize = (long)elements << shift; 370 long pixelSize = getByteCount(); 371 372 if (bufferSize < pixelSize) { 373 throw new RuntimeException("Buffer not large enough for pixels"); 374 } 375 376 nativeCopyPixelsToBuffer(mNativeBitmap, dst); 377 378 // now update the buffer's position 379 int position = dst.position(); 380 position += pixelSize >> shift; 381 dst.position(position); 382 } 383 384 /** 385 * Copy the pixels from the buffer, beginning at the current position, 386 * overwriting the bitmap's pixels. The data in the buffer is not changed 387 * in any way (unlike setPixels(), which converts from unpremultipled 32bit 388 * to whatever the bitmap's native format is. 389 */ 390 public void copyPixelsFromBuffer(Buffer src) { 391 checkRecycled("copyPixelsFromBuffer called on recycled bitmap"); 392 393 int elements = src.remaining(); 394 int shift; 395 if (src instanceof ByteBuffer) { 396 shift = 0; 397 } else if (src instanceof ShortBuffer) { 398 shift = 1; 399 } else if (src instanceof IntBuffer) { 400 shift = 2; 401 } else { 402 throw new RuntimeException("unsupported Buffer subclass"); 403 } 404 405 long bufferBytes = (long)elements << shift; 406 long bitmapBytes = getByteCount(); 407 408 if (bufferBytes < bitmapBytes) { 409 throw new RuntimeException("Buffer not large enough for pixels"); 410 } 411 412 nativeCopyPixelsFromBuffer(mNativeBitmap, src); 413 } 414 415 /** 416 * Tries to make a new bitmap based on the dimensions of this bitmap, 417 * setting the new bitmap's config to the one specified, and then copying 418 * this bitmap's pixels into the new bitmap. If the conversion is not 419 * supported, or the allocator fails, then this returns NULL. The returned 420 * bitmap initially has the same density as the original. 421 * 422 * @param config The desired config for the resulting bitmap 423 * @param isMutable True if the resulting bitmap should be mutable (i.e. 424 * its pixels can be modified) 425 * @return the new bitmap, or null if the copy could not be made. 426 */ 427 public Bitmap copy(Config config, boolean isMutable) { 428 checkRecycled("Can't copy a recycled bitmap"); 429 Bitmap b = nativeCopy(mNativeBitmap, config.nativeInt, isMutable); 430 if (b != null) { 431 b.mDensity = mDensity; 432 } 433 return b; 434 } 435 436 /** 437 * Creates a new bitmap, scaled from an existing bitmap, when possible. If the 438 * specified width and height are the same as the current width and height of 439 * the source btimap, the source bitmap is returned and now new bitmap is 440 * created. 441 * 442 * @param src The source bitmap. 443 * @param dstWidth The new bitmap's desired width. 444 * @param dstHeight The new bitmap's desired height. 445 * @param filter true if the source should be filtered. 446 * @return The new scaled bitmap or the source bitmap if no scaling is required. 447 */ 448 public static Bitmap createScaledBitmap(Bitmap src, int dstWidth, int dstHeight, 449 boolean filter) { 450 Matrix m; 451 synchronized (Bitmap.class) { 452 // small pool of just 1 matrix 453 m = sScaleMatrix; 454 sScaleMatrix = null; 455 } 456 457 if (m == null) { 458 m = new Matrix(); 459 } 460 461 final int width = src.getWidth(); 462 final int height = src.getHeight(); 463 final float sx = dstWidth / (float)width; 464 final float sy = dstHeight / (float)height; 465 m.setScale(sx, sy); 466 Bitmap b = Bitmap.createBitmap(src, 0, 0, width, height, m, filter); 467 468 synchronized (Bitmap.class) { 469 // do we need to check for null? why not just assign everytime? 470 if (sScaleMatrix == null) { 471 sScaleMatrix = m; 472 } 473 } 474 475 return b; 476 } 477 478 /** 479 * Returns an immutable bitmap from the source bitmap. The new bitmap may 480 * be the same object as source, or a copy may have been made. It is 481 * initialized with the same density as the original bitmap. 482 */ 483 public static Bitmap createBitmap(Bitmap src) { 484 return createBitmap(src, 0, 0, src.getWidth(), src.getHeight()); 485 } 486 487 /** 488 * Returns an immutable bitmap from the specified subset of the source 489 * bitmap. The new bitmap may be the same object as source, or a copy may 490 * have been made. It is initialized with the same density as the original 491 * bitmap. 492 * 493 * @param source The bitmap we are subsetting 494 * @param x The x coordinate of the first pixel in source 495 * @param y The y coordinate of the first pixel in source 496 * @param width The number of pixels in each row 497 * @param height The number of rows 498 * @return A copy of a subset of the source bitmap or the source bitmap itself. 499 */ 500 public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height) { 501 return createBitmap(source, x, y, width, height, null, false); 502 } 503 504 /** 505 * Returns an immutable bitmap from subset of the source bitmap, 506 * transformed by the optional matrix. The new bitmap may be the 507 * same object as source, or a copy may have been made. It is 508 * initialized with the same density as the original bitmap. 509 * 510 * If the source bitmap is immutable and the requested subset is the 511 * same as the source bitmap itself, then the source bitmap is 512 * returned and no new bitmap is created. 513 * 514 * @param source The bitmap we are subsetting 515 * @param x The x coordinate of the first pixel in source 516 * @param y The y coordinate of the first pixel in source 517 * @param width The number of pixels in each row 518 * @param height The number of rows 519 * @param m Optional matrix to be applied to the pixels 520 * @param filter true if the source should be filtered. 521 * Only applies if the matrix contains more than just 522 * translation. 523 * @return A bitmap that represents the specified subset of source 524 * @throws IllegalArgumentException if the x, y, width, height values are 525 * outside of the dimensions of the source bitmap. 526 */ 527 public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height, 528 Matrix m, boolean filter) { 529 530 checkXYSign(x, y); 531 checkWidthHeight(width, height); 532 if (x + width > source.getWidth()) { 533 throw new IllegalArgumentException("x + width must be <= bitmap.width()"); 534 } 535 if (y + height > source.getHeight()) { 536 throw new IllegalArgumentException("y + height must be <= bitmap.height()"); 537 } 538 539 // check if we can just return our argument unchanged 540 if (!source.isMutable() && x == 0 && y == 0 && width == source.getWidth() && 541 height == source.getHeight() && (m == null || m.isIdentity())) { 542 return source; 543 } 544 545 int neww = width; 546 int newh = height; 547 Canvas canvas = new Canvas(); 548 Bitmap bitmap; 549 Paint paint; 550 551 Rect srcR = new Rect(x, y, x + width, y + height); 552 RectF dstR = new RectF(0, 0, width, height); 553 554 Config newConfig = Config.ARGB_8888; 555 final Config config = source.getConfig(); 556 // GIF files generate null configs, assume ARGB_8888 557 if (config != null) { 558 switch (config) { 559 case RGB_565: 560 newConfig = Config.RGB_565; 561 break; 562 case ALPHA_8: 563 newConfig = Config.ALPHA_8; 564 break; 565 //noinspection deprecation 566 case ARGB_4444: 567 case ARGB_8888: 568 default: 569 newConfig = Config.ARGB_8888; 570 break; 571 } 572 } 573 574 if (m == null || m.isIdentity()) { 575 bitmap = createBitmap(neww, newh, newConfig, source.hasAlpha()); 576 paint = null; // not needed 577 } else { 578 final boolean transformed = !m.rectStaysRect(); 579 580 RectF deviceR = new RectF(); 581 m.mapRect(deviceR, dstR); 582 583 neww = Math.round(deviceR.width()); 584 newh = Math.round(deviceR.height()); 585 586 bitmap = createBitmap(neww, newh, transformed ? Config.ARGB_8888 : newConfig, 587 transformed || source.hasAlpha()); 588 589 canvas.translate(-deviceR.left, -deviceR.top); 590 canvas.concat(m); 591 592 paint = new Paint(); 593 paint.setFilterBitmap(filter); 594 if (transformed) { 595 paint.setAntiAlias(true); 596 } 597 } 598 599 // The new bitmap was created from a known bitmap source so assume that 600 // they use the same density 601 bitmap.mDensity = source.mDensity; 602 603 canvas.setBitmap(bitmap); 604 canvas.drawBitmap(source, srcR, dstR, paint); 605 canvas.setBitmap(null); 606 607 return bitmap; 608 } 609 610 /** 611 * Returns a mutable bitmap with the specified width and height. Its 612 * initial density is as per {@link #getDensity}. 613 * 614 * @param width The width of the bitmap 615 * @param height The height of the bitmap 616 * @param config The bitmap config to create. 617 * @throws IllegalArgumentException if the width or height are <= 0 618 */ 619 public static Bitmap createBitmap(int width, int height, Config config) { 620 return createBitmap(width, height, config, true); 621 } 622 623 /** 624 * Returns a mutable bitmap with the specified width and height. Its 625 * initial density is as per {@link #getDensity}. 626 * 627 * @param width The width of the bitmap 628 * @param height The height of the bitmap 629 * @param config The bitmap config to create. 630 * @param hasAlpha If the bitmap is ARGB_8888 this flag can be used to mark the 631 * bitmap as opaque. Doing so will clear the bitmap in black 632 * instead of transparent. 633 * 634 * @throws IllegalArgumentException if the width or height are <= 0 635 */ 636 private static Bitmap createBitmap(int width, int height, Config config, boolean hasAlpha) { 637 if (width <= 0 || height <= 0) { 638 throw new IllegalArgumentException("width and height must be > 0"); 639 } 640 Bitmap bm = nativeCreate(null, 0, width, width, height, config.nativeInt, true); 641 if (config == Config.ARGB_8888 && !hasAlpha) { 642 nativeErase(bm.mNativeBitmap, 0xff000000); 643 nativeSetHasAlpha(bm.mNativeBitmap, hasAlpha); 644 } else { 645 // No need to initialize it to zeroes; it is backed by a VM byte array 646 // which is by definition preinitialized to all zeroes. 647 // 648 //nativeErase(bm.mNativeBitmap, 0); 649 } 650 return bm; 651 } 652 653 /** 654 * Returns a immutable bitmap with the specified width and height, with each 655 * pixel value set to the corresponding value in the colors array. Its 656 * initial density is as per {@link #getDensity}. 657 * 658 * @param colors Array of {@link Color} used to initialize the pixels. 659 * @param offset Number of values to skip before the first color in the 660 * array of colors. 661 * @param stride Number of colors in the array between rows (must be >= 662 * width or <= -width). 663 * @param width The width of the bitmap 664 * @param height The height of the bitmap 665 * @param config The bitmap config to create. If the config does not 666 * support per-pixel alpha (e.g. RGB_565), then the alpha 667 * bytes in the colors[] will be ignored (assumed to be FF) 668 * @throws IllegalArgumentException if the width or height are <= 0, or if 669 * the color array's length is less than the number of pixels. 670 */ 671 public static Bitmap createBitmap(int colors[], int offset, int stride, 672 int width, int height, Config config) { 673 674 checkWidthHeight(width, height); 675 if (Math.abs(stride) < width) { 676 throw new IllegalArgumentException("abs(stride) must be >= width"); 677 } 678 int lastScanline = offset + (height - 1) * stride; 679 int length = colors.length; 680 if (offset < 0 || (offset + width > length) || lastScanline < 0 || 681 (lastScanline + width > length)) { 682 throw new ArrayIndexOutOfBoundsException(); 683 } 684 if (width <= 0 || height <= 0) { 685 throw new IllegalArgumentException("width and height must be > 0"); 686 } 687 return nativeCreate(colors, offset, stride, width, height, 688 config.nativeInt, false); 689 } 690 691 /** 692 * Returns a immutable bitmap with the specified width and height, with each 693 * pixel value set to the corresponding value in the colors array. Its 694 * initial density is as per {@link #getDensity}. 695 * 696 * @param colors Array of {@link Color} used to initialize the pixels. 697 * This array must be at least as large as width * height. 698 * @param width The width of the bitmap 699 * @param height The height of the bitmap 700 * @param config The bitmap config to create. If the config does not 701 * support per-pixel alpha (e.g. RGB_565), then the alpha 702 * bytes in the colors[] will be ignored (assumed to be FF) 703 * @throws IllegalArgumentException if the width or height are <= 0, or if 704 * the color array's length is less than the number of pixels. 705 */ 706 public static Bitmap createBitmap(int colors[], int width, int height, Config config) { 707 return createBitmap(colors, 0, width, width, height, config); 708 } 709 710 /** 711 * Returns an optional array of private data, used by the UI system for 712 * some bitmaps. Not intended to be called by applications. 713 */ 714 public byte[] getNinePatchChunk() { 715 return mNinePatchChunk; 716 } 717 718 /** 719 * @hide 720 * @return the layout padding [left, right, top, bottom] 721 */ 722 public int[] getLayoutBounds() { 723 return mLayoutBounds; 724 } 725 726 /** 727 * Specifies the known formats a bitmap can be compressed into 728 */ 729 public enum CompressFormat { 730 JPEG (0), 731 PNG (1), 732 WEBP (2); 733 734 CompressFormat(int nativeInt) { 735 this.nativeInt = nativeInt; 736 } 737 final int nativeInt; 738 } 739 740 /** 741 * Number of bytes of temp storage we use for communicating between the 742 * native compressor and the java OutputStream. 743 */ 744 private final static int WORKING_COMPRESS_STORAGE = 4096; 745 746 /** 747 * Write a compressed version of the bitmap to the specified outputstream. 748 * If this returns true, the bitmap can be reconstructed by passing a 749 * corresponding inputstream to BitmapFactory.decodeStream(). Note: not 750 * all Formats support all bitmap configs directly, so it is possible that 751 * the returned bitmap from BitmapFactory could be in a different bitdepth, 752 * and/or may have lost per-pixel alpha (e.g. JPEG only supports opaque 753 * pixels). 754 * 755 * @param format The format of the compressed image 756 * @param quality Hint to the compressor, 0-100. 0 meaning compress for 757 * small size, 100 meaning compress for max quality. Some 758 * formats, like PNG which is lossless, will ignore the 759 * quality setting 760 * @param stream The outputstream to write the compressed data. 761 * @return true if successfully compressed to the specified stream. 762 */ 763 public boolean compress(CompressFormat format, int quality, OutputStream stream) { 764 checkRecycled("Can't compress a recycled bitmap"); 765 // do explicit check before calling the native method 766 if (stream == null) { 767 throw new NullPointerException(); 768 } 769 if (quality < 0 || quality > 100) { 770 throw new IllegalArgumentException("quality must be 0..100"); 771 } 772 return nativeCompress(mNativeBitmap, format.nativeInt, quality, 773 stream, new byte[WORKING_COMPRESS_STORAGE]); 774 } 775 776 /** 777 * Returns true if the bitmap is marked as mutable (i.e. can be drawn into) 778 */ 779 public final boolean isMutable() { 780 return mIsMutable; 781 } 782 783 /** Returns the bitmap's width */ 784 public final int getWidth() { 785 return mWidth == -1 ? mWidth = nativeWidth(mNativeBitmap) : mWidth; 786 } 787 788 /** Returns the bitmap's height */ 789 public final int getHeight() { 790 return mHeight == -1 ? mHeight = nativeHeight(mNativeBitmap) : mHeight; 791 } 792 793 /** 794 * Convenience for calling {@link #getScaledWidth(int)} with the target 795 * density of the given {@link Canvas}. 796 */ 797 public int getScaledWidth(Canvas canvas) { 798 return scaleFromDensity(getWidth(), mDensity, canvas.mDensity); 799 } 800 801 /** 802 * Convenience for calling {@link #getScaledHeight(int)} with the target 803 * density of the given {@link Canvas}. 804 */ 805 public int getScaledHeight(Canvas canvas) { 806 return scaleFromDensity(getHeight(), mDensity, canvas.mDensity); 807 } 808 809 /** 810 * Convenience for calling {@link #getScaledWidth(int)} with the target 811 * density of the given {@link DisplayMetrics}. 812 */ 813 public int getScaledWidth(DisplayMetrics metrics) { 814 return scaleFromDensity(getWidth(), mDensity, metrics.densityDpi); 815 } 816 817 /** 818 * Convenience for calling {@link #getScaledHeight(int)} with the target 819 * density of the given {@link DisplayMetrics}. 820 */ 821 public int getScaledHeight(DisplayMetrics metrics) { 822 return scaleFromDensity(getHeight(), mDensity, metrics.densityDpi); 823 } 824 825 /** 826 * Convenience method that returns the width of this bitmap divided 827 * by the density scale factor. 828 * 829 * @param targetDensity The density of the target canvas of the bitmap. 830 * @return The scaled width of this bitmap, according to the density scale factor. 831 */ 832 public int getScaledWidth(int targetDensity) { 833 return scaleFromDensity(getWidth(), mDensity, targetDensity); 834 } 835 836 /** 837 * Convenience method that returns the height of this bitmap divided 838 * by the density scale factor. 839 * 840 * @param targetDensity The density of the target canvas of the bitmap. 841 * @return The scaled height of this bitmap, according to the density scale factor. 842 */ 843 public int getScaledHeight(int targetDensity) { 844 return scaleFromDensity(getHeight(), mDensity, targetDensity); 845 } 846 847 /** 848 * @hide 849 */ 850 static public int scaleFromDensity(int size, int sdensity, int tdensity) { 851 if (sdensity == DENSITY_NONE || sdensity == tdensity) { 852 return size; 853 } 854 855 // Scale by tdensity / sdensity, rounding up. 856 return ((size * tdensity) + (sdensity >> 1)) / sdensity; 857 } 858 859 /** 860 * Return the number of bytes between rows in the bitmap's pixels. Note that 861 * this refers to the pixels as stored natively by the bitmap. If you call 862 * getPixels() or setPixels(), then the pixels are uniformly treated as 863 * 32bit values, packed according to the Color class. 864 * 865 * @return number of bytes between rows of the native bitmap pixels. 866 */ 867 public final int getRowBytes() { 868 return nativeRowBytes(mNativeBitmap); 869 } 870 871 /** 872 * Returns the number of bytes used to store this bitmap's pixels. 873 */ 874 public final int getByteCount() { 875 // int result permits bitmaps up to 46,340 x 46,340 876 return getRowBytes() * getHeight(); 877 } 878 879 /** 880 * If the bitmap's internal config is in one of the public formats, return 881 * that config, otherwise return null. 882 */ 883 public final Config getConfig() { 884 return Config.nativeToConfig(nativeConfig(mNativeBitmap)); 885 } 886 887 /** Returns true if the bitmap's config supports per-pixel alpha, and 888 * if the pixels may contain non-opaque alpha values. For some configs, 889 * this is always false (e.g. RGB_565), since they do not support per-pixel 890 * alpha. However, for configs that do, the bitmap may be flagged to be 891 * known that all of its pixels are opaque. In this case hasAlpha() will 892 * also return false. If a config such as ARGB_8888 is not so flagged, 893 * it will return true by default. 894 */ 895 public final boolean hasAlpha() { 896 return nativeHasAlpha(mNativeBitmap); 897 } 898 899 /** 900 * Tell the bitmap if all of the pixels are known to be opaque (false) 901 * or if some of the pixels may contain non-opaque alpha values (true). 902 * Note, for some configs (e.g. RGB_565) this call is ignored, since it 903 * does not support per-pixel alpha values. 904 * 905 * This is meant as a drawing hint, as in some cases a bitmap that is known 906 * to be opaque can take a faster drawing case than one that may have 907 * non-opaque per-pixel alpha values. 908 */ 909 public void setHasAlpha(boolean hasAlpha) { 910 nativeSetHasAlpha(mNativeBitmap, hasAlpha); 911 } 912 913 /** 914 * Fills the bitmap's pixels with the specified {@link Color}. 915 * 916 * @throws IllegalStateException if the bitmap is not mutable. 917 */ 918 public void eraseColor(int c) { 919 checkRecycled("Can't erase a recycled bitmap"); 920 if (!isMutable()) { 921 throw new IllegalStateException("cannot erase immutable bitmaps"); 922 } 923 nativeErase(mNativeBitmap, c); 924 } 925 926 /** 927 * Returns the {@link Color} at the specified location. Throws an exception 928 * if x or y are out of bounds (negative or >= to the width or height 929 * respectively). 930 * 931 * @param x The x coordinate (0...width-1) of the pixel to return 932 * @param y The y coordinate (0...height-1) of the pixel to return 933 * @return The argb {@link Color} at the specified coordinate 934 * @throws IllegalArgumentException if x, y exceed the bitmap's bounds 935 */ 936 public int getPixel(int x, int y) { 937 checkRecycled("Can't call getPixel() on a recycled bitmap"); 938 checkPixelAccess(x, y); 939 return nativeGetPixel(mNativeBitmap, x, y); 940 } 941 942 /** 943 * Returns in pixels[] a copy of the data in the bitmap. Each value is 944 * a packed int representing a {@link Color}. The stride parameter allows 945 * the caller to allow for gaps in the returned pixels array between 946 * rows. For normal packed results, just pass width for the stride value. 947 * 948 * @param pixels The array to receive the bitmap's colors 949 * @param offset The first index to write into pixels[] 950 * @param stride The number of entries in pixels[] to skip between 951 * rows (must be >= bitmap's width). Can be negative. 952 * @param x The x coordinate of the first pixel to read from 953 * the bitmap 954 * @param y The y coordinate of the first pixel to read from 955 * the bitmap 956 * @param width The number of pixels to read from each row 957 * @param height The number of rows to read 958 * @throws IllegalArgumentException if x, y, width, height exceed the 959 * bounds of the bitmap, or if abs(stride) < width. 960 * @throws ArrayIndexOutOfBoundsException if the pixels array is too small 961 * to receive the specified number of pixels. 962 */ 963 public void getPixels(int[] pixels, int offset, int stride, 964 int x, int y, int width, int height) { 965 checkRecycled("Can't call getPixels() on a recycled bitmap"); 966 if (width == 0 || height == 0) { 967 return; // nothing to do 968 } 969 checkPixelsAccess(x, y, width, height, offset, stride, pixels); 970 nativeGetPixels(mNativeBitmap, pixels, offset, stride, 971 x, y, width, height); 972 } 973 974 /** 975 * Shared code to check for illegal arguments passed to getPixel() 976 * or setPixel() 977 * @param x x coordinate of the pixel 978 * @param y y coordinate of the pixel 979 */ 980 private void checkPixelAccess(int x, int y) { 981 checkXYSign(x, y); 982 if (x >= getWidth()) { 983 throw new IllegalArgumentException("x must be < bitmap.width()"); 984 } 985 if (y >= getHeight()) { 986 throw new IllegalArgumentException("y must be < bitmap.height()"); 987 } 988 } 989 990 /** 991 * Shared code to check for illegal arguments passed to getPixels() 992 * or setPixels() 993 * 994 * @param x left edge of the area of pixels to access 995 * @param y top edge of the area of pixels to access 996 * @param width width of the area of pixels to access 997 * @param height height of the area of pixels to access 998 * @param offset offset into pixels[] array 999 * @param stride number of elements in pixels[] between each logical row 1000 * @param pixels array to hold the area of pixels being accessed 1001 */ 1002 private void checkPixelsAccess(int x, int y, int width, int height, 1003 int offset, int stride, int pixels[]) { 1004 checkXYSign(x, y); 1005 if (width < 0) { 1006 throw new IllegalArgumentException("width must be >= 0"); 1007 } 1008 if (height < 0) { 1009 throw new IllegalArgumentException("height must be >= 0"); 1010 } 1011 if (x + width > getWidth()) { 1012 throw new IllegalArgumentException( 1013 "x + width must be <= bitmap.width()"); 1014 } 1015 if (y + height > getHeight()) { 1016 throw new IllegalArgumentException( 1017 "y + height must be <= bitmap.height()"); 1018 } 1019 if (Math.abs(stride) < width) { 1020 throw new IllegalArgumentException("abs(stride) must be >= width"); 1021 } 1022 int lastScanline = offset + (height - 1) * stride; 1023 int length = pixels.length; 1024 if (offset < 0 || (offset + width > length) 1025 || lastScanline < 0 1026 || (lastScanline + width > length)) { 1027 throw new ArrayIndexOutOfBoundsException(); 1028 } 1029 } 1030 1031 /** 1032 * Write the specified {@link Color} into the bitmap (assuming it is 1033 * mutable) at the x,y coordinate. 1034 * 1035 * @param x The x coordinate of the pixel to replace (0...width-1) 1036 * @param y The y coordinate of the pixel to replace (0...height-1) 1037 * @param color The {@link Color} to write into the bitmap 1038 * @throws IllegalStateException if the bitmap is not mutable 1039 * @throws IllegalArgumentException if x, y are outside of the bitmap's 1040 * bounds. 1041 */ 1042 public void setPixel(int x, int y, int color) { 1043 checkRecycled("Can't call setPixel() on a recycled bitmap"); 1044 if (!isMutable()) { 1045 throw new IllegalStateException(); 1046 } 1047 checkPixelAccess(x, y); 1048 nativeSetPixel(mNativeBitmap, x, y, color); 1049 } 1050 1051 /** 1052 * Replace pixels in the bitmap with the colors in the array. Each element 1053 * in the array is a packed int prepresenting a {@link Color} 1054 * 1055 * @param pixels The colors to write to the bitmap 1056 * @param offset The index of the first color to read from pixels[] 1057 * @param stride The number of colors in pixels[] to skip between rows. 1058 * Normally this value will be the same as the width of 1059 * the bitmap, but it can be larger (or negative). 1060 * @param x The x coordinate of the first pixel to write to in 1061 * the bitmap. 1062 * @param y The y coordinate of the first pixel to write to in 1063 * the bitmap. 1064 * @param width The number of colors to copy from pixels[] per row 1065 * @param height The number of rows to write to the bitmap 1066 * @throws IllegalStateException if the bitmap is not mutable 1067 * @throws IllegalArgumentException if x, y, width, height are outside of 1068 * the bitmap's bounds. 1069 * @throws ArrayIndexOutOfBoundsException if the pixels array is too small 1070 * to receive the specified number of pixels. 1071 */ 1072 public void setPixels(int[] pixels, int offset, int stride, 1073 int x, int y, int width, int height) { 1074 checkRecycled("Can't call setPixels() on a recycled bitmap"); 1075 if (!isMutable()) { 1076 throw new IllegalStateException(); 1077 } 1078 if (width == 0 || height == 0) { 1079 return; // nothing to do 1080 } 1081 checkPixelsAccess(x, y, width, height, offset, stride, pixels); 1082 nativeSetPixels(mNativeBitmap, pixels, offset, stride, 1083 x, y, width, height); 1084 } 1085 1086 public static final Parcelable.Creator<Bitmap> CREATOR 1087 = new Parcelable.Creator<Bitmap>() { 1088 /** 1089 * Rebuilds a bitmap previously stored with writeToParcel(). 1090 * 1091 * @param p Parcel object to read the bitmap from 1092 * @return a new bitmap created from the data in the parcel 1093 */ 1094 public Bitmap createFromParcel(Parcel p) { 1095 Bitmap bm = nativeCreateFromParcel(p); 1096 if (bm == null) { 1097 throw new RuntimeException("Failed to unparcel Bitmap"); 1098 } 1099 return bm; 1100 } 1101 public Bitmap[] newArray(int size) { 1102 return new Bitmap[size]; 1103 } 1104 }; 1105 1106 /** 1107 * No special parcel contents. 1108 */ 1109 public int describeContents() { 1110 return 0; 1111 } 1112 1113 /** 1114 * Write the bitmap and its pixels to the parcel. The bitmap can be 1115 * rebuilt from the parcel by calling CREATOR.createFromParcel(). 1116 * @param p Parcel object to write the bitmap data into 1117 */ 1118 public void writeToParcel(Parcel p, int flags) { 1119 checkRecycled("Can't parcel a recycled bitmap"); 1120 if (!nativeWriteToParcel(mNativeBitmap, mIsMutable, mDensity, p)) { 1121 throw new RuntimeException("native writeToParcel failed"); 1122 } 1123 } 1124 1125 /** 1126 * Returns a new bitmap that captures the alpha values of the original. 1127 * This may be drawn with Canvas.drawBitmap(), where the color(s) will be 1128 * taken from the paint that is passed to the draw call. 1129 * 1130 * @return new bitmap containing the alpha channel of the original bitmap. 1131 */ 1132 public Bitmap extractAlpha() { 1133 return extractAlpha(null, null); 1134 } 1135 1136 /** 1137 * Returns a new bitmap that captures the alpha values of the original. 1138 * These values may be affected by the optional Paint parameter, which 1139 * can contain its own alpha, and may also contain a MaskFilter which 1140 * could change the actual dimensions of the resulting bitmap (e.g. 1141 * a blur maskfilter might enlarge the resulting bitmap). If offsetXY 1142 * is not null, it returns the amount to offset the returned bitmap so 1143 * that it will logically align with the original. For example, if the 1144 * paint contains a blur of radius 2, then offsetXY[] would contains 1145 * -2, -2, so that drawing the alpha bitmap offset by (-2, -2) and then 1146 * drawing the original would result in the blur visually aligning with 1147 * the original. 1148 * 1149 * <p>The initial density of the returned bitmap is the same as the original's. 1150 * 1151 * @param paint Optional paint used to modify the alpha values in the 1152 * resulting bitmap. Pass null for default behavior. 1153 * @param offsetXY Optional array that returns the X (index 0) and Y 1154 * (index 1) offset needed to position the returned bitmap 1155 * so that it visually lines up with the original. 1156 * @return new bitmap containing the (optionally modified by paint) alpha 1157 * channel of the original bitmap. This may be drawn with 1158 * Canvas.drawBitmap(), where the color(s) will be taken from the 1159 * paint that is passed to the draw call. 1160 */ 1161 public Bitmap extractAlpha(Paint paint, int[] offsetXY) { 1162 checkRecycled("Can't extractAlpha on a recycled bitmap"); 1163 int nativePaint = paint != null ? paint.mNativePaint : 0; 1164 Bitmap bm = nativeExtractAlpha(mNativeBitmap, nativePaint, offsetXY); 1165 if (bm == null) { 1166 throw new RuntimeException("Failed to extractAlpha on Bitmap"); 1167 } 1168 bm.mDensity = mDensity; 1169 return bm; 1170 } 1171 1172 /** 1173 * Given another bitmap, return true if it has the same dimensions, config, 1174 * and pixel data as this bitmap. If any of those differ, return false. 1175 * If other is null, return false. 1176 */ 1177 public boolean sameAs(Bitmap other) { 1178 return this == other || (other != null && nativeSameAs(mNativeBitmap, other.mNativeBitmap)); 1179 } 1180 1181 /** 1182 * Rebuilds any caches associated with the bitmap that are used for 1183 * drawing it. In the case of purgeable bitmaps, this call will attempt to 1184 * ensure that the pixels have been decoded. 1185 * If this is called on more than one bitmap in sequence, the priority is 1186 * given in LRU order (i.e. the last bitmap called will be given highest 1187 * priority). 1188 * 1189 * For bitmaps with no associated caches, this call is effectively a no-op, 1190 * and therefore is harmless. 1191 */ 1192 public void prepareToDraw() { 1193 nativePrepareToDraw(mNativeBitmap); 1194 } 1195 1196 private static class BitmapFinalizer { 1197 private final int mNativeBitmap; 1198 1199 BitmapFinalizer(int nativeBitmap) { 1200 mNativeBitmap = nativeBitmap; 1201 } 1202 1203 @Override 1204 public void finalize() { 1205 try { 1206 super.finalize(); 1207 } catch (Throwable t) { 1208 // Ignore 1209 } finally { 1210 nativeDestructor(mNativeBitmap); 1211 } 1212 } 1213 } 1214 1215 //////////// native methods 1216 1217 private static native Bitmap nativeCreate(int[] colors, int offset, 1218 int stride, int width, int height, 1219 int nativeConfig, boolean mutable); 1220 private static native Bitmap nativeCopy(int srcBitmap, int nativeConfig, 1221 boolean isMutable); 1222 private static native void nativeDestructor(int nativeBitmap); 1223 private static native void nativeRecycle(int nativeBitmap); 1224 1225 private static native boolean nativeCompress(int nativeBitmap, int format, 1226 int quality, OutputStream stream, 1227 byte[] tempStorage); 1228 private static native void nativeErase(int nativeBitmap, int color); 1229 private static native int nativeWidth(int nativeBitmap); 1230 private static native int nativeHeight(int nativeBitmap); 1231 private static native int nativeRowBytes(int nativeBitmap); 1232 private static native int nativeConfig(int nativeBitmap); 1233 private static native boolean nativeHasAlpha(int nativeBitmap); 1234 1235 private static native int nativeGetPixel(int nativeBitmap, int x, int y); 1236 private static native void nativeGetPixels(int nativeBitmap, int[] pixels, 1237 int offset, int stride, int x, 1238 int y, int width, int height); 1239 1240 private static native void nativeSetPixel(int nativeBitmap, int x, int y, 1241 int color); 1242 private static native void nativeSetPixels(int nativeBitmap, int[] colors, 1243 int offset, int stride, int x, 1244 int y, int width, int height); 1245 private static native void nativeCopyPixelsToBuffer(int nativeBitmap, 1246 Buffer dst); 1247 private static native void nativeCopyPixelsFromBuffer(int nb, Buffer src); 1248 private static native int nativeGenerationId(int nativeBitmap); 1249 1250 private static native Bitmap nativeCreateFromParcel(Parcel p); 1251 // returns true on success 1252 private static native boolean nativeWriteToParcel(int nativeBitmap, 1253 boolean isMutable, 1254 int density, 1255 Parcel p); 1256 // returns a new bitmap built from the native bitmap's alpha, and the paint 1257 private static native Bitmap nativeExtractAlpha(int nativeBitmap, 1258 int nativePaint, 1259 int[] offsetXY); 1260 1261 private static native void nativePrepareToDraw(int nativeBitmap); 1262 private static native void nativeSetHasAlpha(int nBitmap, boolean hasAlpha); 1263 private static native boolean nativeSameAs(int nb0, int nb1); 1264 1265 /* package */ final int ni() { 1266 return mNativeBitmap; 1267 } 1268 } 1269
